With the switch over to nolibc the source file vdso_standalone_test_x86.c
was intended to be replaced with a symlink to vdso_test_gettimeofday.c.
This was the patch that was submitted to LKML, but during application the
symlink was replaced by a textual copy of the linked-to file.
Having two copies introduces the possibility of divergence and increases
maintenance burden, switch back to a symlink.
Fixes: 8770a9183f ("selftests: vDSO: vdso_standalone_test_x86: Switch to nolibc")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20250226-parse_vdso-nolibc-v2-16-28e14e031ed8@linutronix.de/
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-9-e62e37a6bcf5@linutronix.de
The TAP specification requires that the output begins with a header line.
If vgetrandom_init() fails and skips the test, that header line is missing.
Call vgetrandom_init() after ksft_print_header().
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-8-e62e37a6bcf5@linutronix.de
Functions definitions without any argument list produce a warning with
-Wstrict-prototypes:
vdso_test_correctness.c:111:13: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
111 | static void fill_function_pointers()
| ^~~~~~~~~~~~~~~~~~~~~~
Explicitly use an empty argument list.
Now that all selftests a free of this warning, enable it in the Makefile.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-7-e62e37a6bcf5@linutronix.de
Not all users of this header make use of all its variables.
For example vdso_test_correctness.c does not use "versions":
In file included from vdso_test_correctness.c:22:
vdso_config.h:61:20: warning: ‘versions’ defined but not used [-Wunused-variable]
61 | static const char *versions[7] = {
| ^~~~~~~~
Avoid those warnings through attribute((unused)).
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-5-e62e37a6bcf5@linutronix.de
vgetrandom_put_state() and the variable "ret" in kselftest() are unused.
Drop the variable "ret". Suppress the warning for vgetrandom_put_state()
as it is meant as an example for libc implementors.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-4-e62e37a6bcf5@linutronix.de
The header is unused. Furthermore this is not a real UAPI header,
but only exists in tools/include/.
This prevents building the selftest against real UAPI headers.
Drop the include.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-3-e62e37a6bcf5@linutronix.de
According to kselftest.h ksft_exit_skip() is not meant to be called when
a plan has already been printed.
Use the recommended function ksft_test_result_skip().
This fixes a bug, where the TAP output would be invalid when skipping:
TAP version 13
1..1
ok 2 # SKIP Not implemented on architecture
The SKIP line should start with "ok 1" as the plan only contains one test.
Fixes: 3b5992eaf7 ("selftests: vDSO: unconditionally build chacha test")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/all/20250611-selftests-vdso-fixes-v3-1-e62e37a6bcf5@linutronix.de
Hook up the generic vDSO implementation to the generic vDSO getrandom
implementation by providing the required __arch_chacha20_blocks_nostack
and getrandom_syscall implementations. Also wire up the selftests.
The benchmark result:
vdso: 25000000 times in 2.466341333 seconds
libc: 25000000 times in 41.447720005 seconds
syscall: 25000000 times in 41.043926672 seconds
vdso: 25000000 x 256 times in 162.286219353 seconds
libc: 25000000 x 256 times in 2953.855018685 seconds
syscall: 25000000 x 256 times in 2796.268546000 seconds
[ alex: - Fix dynamic relocation
- Squash Nathan's fix https://lore.kernel.org/all/20250423-riscv-fix-compat_vdso-lld-v2-1-b7bbbc244501@kernel.org/
- Add comment from Loongarch ]
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Link: https://lore.kernel.org/r/20250411024600.16045-1-xry111@xry111.site
Tested-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
- Consolidate the VDSO storage
The VDSO data storage and data layout has been largely architecture
specific for historical reasons. That increases the maintenance effort
and causes inconsistencies over and over.
There is no real technical reason for architecture specific layouts and
implementations. The architecture specific details can easily be
integrated into a generic layout, which also reduces the amount of
duplicated code for managing the mappings.
Convert all architectures over to a unified layout and common mapping
infrastructure. This splits the VDSO data layout into subsystem
specific blocks, timekeeping, random and architecture parts, which
provides a better structure and allows to improve and update the
functionalities without conflict and interaction.
- Rework the timekeeping data storage
The current implementation is designed for exposing system timekeeping
accessors, which was good enough at the time when it was designed.
PTP and Time Sensitive Networking (TSN) change that as there are
requirements to expose independent PTP clocks, which are not related to
system timekeeping.
Replace the monolithic data storage by a structured layout, which
allows to add support for independent PTP clocks on top while reusing
both the data structures and the time accessor implementations.
-----BEGIN PGP SIGNATURE-----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=rwei
-----END PGP SIGNATURE-----
Merge tag 'timers-vdso-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull VDSO infrastructure updates from Thomas Gleixner:
- Consolidate the VDSO storage
The VDSO data storage and data layout has been largely architecture
specific for historical reasons. That increases the maintenance
effort and causes inconsistencies over and over.
There is no real technical reason for architecture specific layouts
and implementations. The architecture specific details can easily be
integrated into a generic layout, which also reduces the amount of
duplicated code for managing the mappings.
Convert all architectures over to a unified layout and common mapping
infrastructure. This splits the VDSO data layout into subsystem
specific blocks, timekeeping, random and architecture parts, which
provides a better structure and allows to improve and update the
functionalities without conflict and interaction.
- Rework the timekeeping data storage
The current implementation is designed for exposing system
timekeeping accessors, which was good enough at the time when it was
designed.
PTP and Time Sensitive Networking (TSN) change that as there are
requirements to expose independent PTP clocks, which are not related
to system timekeeping.
Replace the monolithic data storage by a structured layout, which
allows to add support for independent PTP clocks on top while reusing
both the data structures and the time accessor implementations.
* tag 'timers-vdso-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
sparc/vdso: Always reject undefined references during linking
x86/vdso: Always reject undefined references during linking
vdso: Rework struct vdso_time_data and introduce struct vdso_clock
vdso: Move architecture related data before basetime data
powerpc/vdso: Prepare introduction of struct vdso_clock
arm64/vdso: Prepare introduction of struct vdso_clock
x86/vdso: Prepare introduction of struct vdso_clock
time/namespace: Prepare introduction of struct vdso_clock
vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock struct
vdso/vsyscall: Prepare introduction of struct vdso_clock
vdso/gettimeofday: Prepare helper functions for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_coarse_timens() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_coarse() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_hres_timens() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare do_hres() for introduction of struct vdso_clock
vdso/gettimeofday: Prepare introduction of struct vdso_clock
vdso/helpers: Prepare introduction of struct vdso_clock
vdso/datapage: Define vdso_clock to prepare for multiple PTP clocks
vdso: Make vdso_time_data cacheline aligned
arm64: Make asm/cache.h compatible with vDSO
...
Commit 14be4e6f35 ("selftests: vDSO: fix ELF hash table entry size for s390x")
changed the type of the ELF hash table entries to 64bit on s390x.
However the *GNU* hash tables entries are always 32bit.
The "bucket" pointer is shared between both hash algorithms.
On s390, this caused the GNU hash algorithm to access its 32-bit entries as if they
were 64-bit, triggering compiler warnings (assignment between "Elf64_Xword *" and
"Elf64_Word *") and runtime crashes.
Introduce a new dedicated "gnu_bucket" pointer which is used by the GNU hash.
Fixes: e0746bde6f ("selftests/vDSO: support DT_GNU_HASH")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250217-selftests-vdso-s390-gnu-hash-v2-1-f6c2532ffe2a@linutronix.de
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
vdso_standalone_test_x86 provides its own ASM syscall wrappers and
_start() implementation. The in-tree nolibc library already provides
this functionality for multiple architectures. By making use of nolibc,
the standalone testcase can be built from the exact same codebase as the
non-standalone version.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-16-28e14e031ed8@linutronix.de
nolibc does not provide sys/time.h and sys/auxv.h,
instead their definitions are available unconditionally.
Guard the includes so they are not attempted on nolibc.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-15-28e14e031ed8@linutronix.de
According to limits.h(2) ULONG_MAX is only guaranteed to expand to an
expression, not a symbolic constant which can be evaluated by the
preprocessor.
Specifically the definition of ULONG_MAX from nolibc can not be evaluated
by the preprocessor. To provide compatibility with nolibc, check with
__SIZEOF_LONG__ instead, with is provided directly by the preprocessor
and therefore always a symbolic constant.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-13-28e14e031ed8@linutronix.de
To allow the usage of parse_vdso.c together with a limited libc like
nolibc, use the kernels own elf.h and auxvec.h headers.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-12-28e14e031ed8@linutronix.de
There are no users left.
This also removes the usage of ElfXX_auxv_t, which is not formally
standardized.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-11-28e14e031ed8@linutronix.de
vdso_standalone_test_x86 is the only user of vdso_init_from_auxv().
Instead of combining the parsing the aux vector with the parsing of the
vDSO, split them apart into getauxval() and the regular
vdso_init_from_sysinfo_ehdr().
The implementation of getauxval() is taken from
tools/include/nolibc/stdlib.h.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/all/20250226-parse_vdso-nolibc-v2-10-28e14e031ed8@linutronix.de
glibc added support for DT_GNU_HASH in 2006 and DT_HASH has been
obsoleted for more than one decade in many Linux distributions.
Many vDSOs support DT_GNU_HASH. This patch adds selftests support.
Link: https://lore.kernel.org/r/20241206130724.7944-2-xry111@xry111.site
Signed-off-by: Fangrui Song <i@maskray.me>
Tested-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Xi Ruoyao <xry111@xry111.site> # rebase
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
- Rework kfence support for the HPT MMU to work on systems with >= 16TB of RAM.
- Remove the powerpc "maple" platform, used by the "Yellow Dog Powerstation".
- Add support for DYNAMIC_FTRACE_WITH_CALL_OPS,
DYNAMIC_FTRACE_WITH_DIRECT_CALLS & BPF Trampolines.
- Add support for running KVM nested guests on Power11.
- Other small features, cleanups and fixes.
Thanks to: Amit Machhiwal, Arnd Bergmann, Christophe Leroy, Costa Shulyupin,
David Hunter, David Wang, Disha Goel, Gautam Menghani, Geert Uytterhoeven,
Hari Bathini, Julia Lawall, Kajol Jain, Keith Packard, Lukas Bulwahn, Madhavan
Srinivasan, Markus Elfring, Michal Suchanek, Ming Lei, Mukesh Kumar Chaurasiya,
Nathan Chancellor, Naveen N Rao, Nicholas Piggin, Nysal Jan K.A, Paulo Miguel
Almeida, Pavithra Prakash, Ritesh Harjani (IBM), Rob Herring (Arm), Sachin P
Bappalige, Shen Lichuan, Simon Horman, Sourabh Jain, Thomas Weißschuh, Thorsten
Blum, Thorsten Leemhuis, Venkat Rao Bagalkote, Zhang Zekun,
zhang jiao.
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRjvi15rv0TSTaE+SIF0oADX8seIQUCZ0Fi5AAKCRAF0oADX8se
IeI0AQCAkNWRYzGNzPM6aMwDpq5qdeZzvp0rZxuNsRSnIKJlxAD+PAOxOietgjbQ
Lxt3oizg+UcH/304Y/iyT8IrwI4n+gE=
=xNtu
-----END PGP SIGNATURE-----
Merge tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Rework kfence support for the HPT MMU to work on systems with >= 16TB
of RAM.
- Remove the powerpc "maple" platform, used by the "Yellow Dog
Powerstation".
- Add support for DYNAMIC_FTRACE_WITH_CALL_OPS,
DYNAMIC_FTRACE_WITH_DIRECT_CALLS & BPF Trampolines.
- Add support for running KVM nested guests on Power11.
- Other small features, cleanups and fixes.
Thanks to Amit Machhiwal, Arnd Bergmann, Christophe Leroy, Costa
Shulyupin, David Hunter, David Wang, Disha Goel, Gautam Menghani, Geert
Uytterhoeven, Hari Bathini, Julia Lawall, Kajol Jain, Keith Packard,
Lukas Bulwahn, Madhavan Srinivasan, Markus Elfring, Michal Suchanek,
Ming Lei, Mukesh Kumar Chaurasiya, Nathan Chancellor, Naveen N Rao,
Nicholas Piggin, Nysal Jan K.A, Paulo Miguel Almeida, Pavithra Prakash,
Ritesh Harjani (IBM), Rob Herring (Arm), Sachin P Bappalige, Shen
Lichuan, Simon Horman, Sourabh Jain, Thomas Weißschuh, Thorsten Blum,
Thorsten Leemhuis, Venkat Rao Bagalkote, Zhang Zekun, and zhang jiao.
* tag 'powerpc-6.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (89 commits)
EDAC/powerpc: Remove PPC_MAPLE drivers
powerpc/perf: Add per-task/process monitoring to vpa_pmu driver
powerpc/kvm: Add vpa latency counters to kvm_vcpu_arch
docs: ABI: sysfs-bus-event_source-devices-vpa-pmu: Document sysfs event format entries for vpa_pmu
powerpc/perf: Add perf interface to expose vpa counters
MAINTAINERS: powerpc: Mark Maddy as "M"
powerpc/Makefile: Allow overriding CPP
powerpc-km82xx.c: replace of_node_put() with __free
ps3: Correct some typos in comments
powerpc/kexec: Fix return of uninitialized variable
macintosh: Use common error handling code in via_pmu_led_init()
powerpc/powermac: Use of_property_match_string() in pmac_has_backlight_type()
powerpc: remove dead config options for MPC85xx platform support
powerpc/xive: Use cpumask_intersects()
selftests/powerpc: Remove the path after initialization.
powerpc/xmon: symbol lookup length fixed
powerpc/ep8248e: Use %pa to format resource_size_t
powerpc/ps3: Reorganize kerneldoc parameter names
KVM: PPC: Book3S HV: Fix kmv -> kvm typo
powerpc/sstep: make emulate_vsx_load and emulate_vsx_store static
...
On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.
$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: PowerPC64
Version: 0x1
...
Symbol table '.dynsym' contains 12 entries:
Num: Value Size Type Bind Vis Ndx Name
...
1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
...
4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
Symbol table '.symtab' contains 56 entries:
Num: Value Size Type Bind Vis Ndx Name
...
45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu
47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres
To overcome that, commit ba83b3239e ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.
The original commit that brought VDSO support into powerpc/64 has the
following explanation:
Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
can't be expected to link against them directly, the vDSO's are both seen
as if they were linked at 0 and the symbols just contain offsets to the
various functions. This is done on purpose to avoid a relocation step
(ppc64 functions normally have descriptors with abs addresses in them).
When glibc uses those functions, it's expected to use it's own trampolines
that know how to reach them.
The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.
glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.
For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.
So lets flag VDSO entry points as functions and revert the
selftest change.
Link: 5f2dd691b6
Fixes: ba83b3239e ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-By: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
The previous commit introduced the use of CLONE_NEWTIME without including
<sched.h> which contains its definition.
Add an explicit include of <sched.h> to ensure that CLONE_NEWTIME
is correctly defined before it is used.
Fixes: 2aec90036d ("selftests: vDSO: ensure vgetrandom works in a time namespace")
Signed-off-by: Yu Liao <liaoyu15@huawei.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Improve the error and skip condition messages to let the developer know
precisely where a test has failed. Also make better use of the ksft api
for this.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Rather than building on supported archs, build on all archs, and then
use the presence of the symbol in the vDSO to either skip the test or
move forward with it.
Note that this means that this test no longer checks whether the symbol
was correctly added to the kernel. But hopefully this will be clear
enough to developers and we'll cross our fingers that symbols aren't
removed by accident and not caught after this change.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Rather than using symlinks to find the vgetrandom-chacha.S file for each
arch, store this in a file that uses the compiler to determine
architecture, and then make use of weak symbols to skip the test on
architectures that don't provide the code.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This prevents false sharing, which makes a large difference on machines
with several NUMA nodes, such as on a dual socket Intel(R) Xeon(R) Gold
6338 CPU @ 2.00GHz, where the "bench-multi" test goes from 2.7s down to
1.9s. While this is just test code, it also forms the basis of how folks
will wind up implementing this in libraries, so we should implement this
simple cache alignment improvement here.
Suggested-by: Florian Weimer <fweimer@redhat.com>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This kselftest fixes update for Linux 6.12-rc1 consists of an urgent
fix to vDSO as automated testing is failing due to this bug.
-----BEGIN PGP SIGNATURE-----
iQIzBAABCgAdFiEEPZKym/RZuOCGeA/kCwJExA0NQxwFAmb4P5QACgkQCwJExA0N
QxzEuhAA2GBjNFXfIMSMxXsnHMXYpkJ3kPzf83kVbZK/RSFPE5k4X9Yo1isUJTeJ
xshljPKVcpA6KSDdBXl4tV3/KAwpf0t9CGHJYNkMmVXHe1NDUXcqe1htFr6FcYos
yMSoURGZCANMUIeqZ2e+uj87P1tMFVdELIen8DZ92g6el8Jp13VmVyRxPyIcdZtt
rVE5SFIw/2VflTWKni0N5jaL2MdUu/xxTguUUcwBR9zhgJlAMXxeKfWTgdVFeeVW
TxSzTGweCizmKSm1t2ncT8LGu1Zpvjex1k7lzcvwdcXm1t0ssFstAsKgHw8q3J6Q
Rp2SOUcK4CraCNzXeMbkenX/wlmyXiph27i0pH0I22lFzI+IHCjYnKazLPYNhUK5
K1rSjkrnZDI6+ZJ2NUkAMkq6bn+YUbmqeWaX8k+ybZNbZaXaADymlEBIP5Kzwmmz
MU+tO2BT6lXsdW2w7wIgqkH8vmw5V5CFhPvioiKPKhGdKmDR6FrLlYEjY61Uzy3i
nlQO87z1/b6qIDFsc6I6NvYwDFGRCH4ensCtCmJTleX1NAqICATZtD0bqB6NEFXn
Slu2pykzjlaChZBPpGVC8WaAHprANZoiDBwpdeHOZ6a7xcflEWLSsmcGGtWc7JdN
uTUcz4x7Mn/0LlcOGELIs3r3bUwziXvp9uN3Mm4xO5lp26U1cKo=
=vFbG
-----END PGP SIGNATURE-----
Merge tag 'linux_kselftest-next-6.12-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest fix from Shuah Khan:
"One urgent fix to vDSO as automated testing is failing due to this
bug"
* tag 'linux_kselftest-next-6.12-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests: vDSO: align stack for O2-optimized memcpy
When switching on -O2, gcc generates SSE2 instructions that assume a
16-byte aligned stack, which the standalone test's start point wasn't
aligning. Fix this with the usual alignment sequence.
Fixes: ecb8bd70d5 ("selftests: vDSO: build tests with O2 optimization")
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202409241558.98e13f6f-oliver.sang@intel.com
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Some archs -- arm64 and s390x -- implemented chacha using instructions
that are available most places, but aren't always available. The kernel
handles this just fine, but the selftest does not. Check the hwcaps
before running, and skip the test if the cpu doesn't support it. As
well, on s390x, always emit the fallback instructions of an alternative
block, to ensure maximum compatibility.
Co-developed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Provide the s390 specific vdso getrandom() architecture backend.
_vdso_rng_data required data is placed within the _vdso_data vvar page,
by using a hardcoded offset larger than vdso_data.
As required the chacha20 implementation does not write to the stack.
The implementation follows more or less the arm64 implementations and
makes use of vector instructions. It has a fallback to the getrandom()
system call for machines where the vector facility is not installed.
The check if the vector facility is installed, as well as an
optimization for machines with the vector-enhancements facility 2, is
implemented with alternatives, avoiding runtime checks.
Note that __kernel_getrandom() is implemented without the vdso user
wrapper which would setup a stack frame for odd cases (aka very old
glibc variants) where the caller has not done that. All callers of
__kernel_getrandom() are required to setup a stack frame, like the C ABI
requires it.
The vdso testcases vdso_test_getrandom and vdso_test_chacha pass.
Benchmark on a z16:
$ ./vdso_test_getrandom bench-single
vdso: 25000000 times in 0.493703559 seconds
syscall: 25000000 times in 6.584025337 seconds
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Running vdso_test_correctness on s390x (aka s390 64 bit) emits a warning:
Warning: failed to find clock_gettime64 in vDSO
This is caused by the "#elif defined (__s390__)" check in vdso_config.h
which the defines VDSO_32BIT.
If __s390x__ is defined also __s390__ is defined. Therefore the correct
check must make sure that only __s390__ is defined.
Therefore add the missing !defined(__s390x__). Also use common
__s390x__ define instead of __s390X__.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Fixes: 693f5ca08c ("kselftest: Extend vDSO selftest")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The vDSO self tests fail on s390x for a vDSO linked with the GNU linker
ld as follows:
# ./vdso_test_gettimeofday
Floating point exception (core dumped)
On s390x the ELF hash table entries are 64 bits instead of 32 bits in
size (see Glibc sysdeps/unix/sysv/linux/s390/bits/elfclass.h).
Fixes: 40723419f4 ("kselftest: Enable vDSO test on non x86 platforms")
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
To be consistent with other VDSO functions, the function is called
__kernel_getrandom()
__arch_chacha20_blocks_nostack() fonction is implemented basically
with 32 bits operations. It performs 4 QUARTERROUND operations in
parallele. There are enough registers to avoid using the stack:
On input:
r3: output bytes
r4: 32-byte key input
r5: 8-byte counter input/output
r6: number of 64-byte blocks to write to output
During operation:
stack: pointer to counter (r5) and non-volatile registers (r14-131)
r0: counter of blocks (initialised with r6)
r4: Value '4' after key has been read, used for indexing
r5-r12: key
r14-r15: block counter
r16-r31: chacha state
At the end:
r0, r6-r12: Zeroised
r5, r14-r31: Restored
Performance on powerpc 885 (using kernel selftest):
~# ./vdso_test_getrandom bench-single
vdso: 25000000 times in 62.938002291 seconds
libc: 25000000 times in 535.581916866 seconds
syscall: 25000000 times in 531.525042806 seconds
Performance on powerpc 8321 (using kernel selftest):
~# ./vdso_test_getrandom bench-single
vdso: 25000000 times in 16.899318858 seconds
libc: 25000000 times in 131.050596522 seconds
syscall: 25000000 times in 129.794790389 seconds
This first patch adds support for VDSO32. As selftests cannot easily
be generated only for VDSO32, and because the following patch brings
support for VDSO64 anyway, this patch opts out all code in
__arch_chacha20_blocks_nostack() so that vdso_test_chacha will not
fail to compile and will not crash on PPC64/PPC64LE, allthough the
selftest itself will fail.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
It's not correct to use $(top_srcdir) for generated header files, for
builds that are done out of tree via O=, and $(objtree) isn't valid in
the selftests context. Instead, just obviate the need for these
generated header files by defining empty stubs in tools/include, which
is the same thing that's done for rwlock.h.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Hook up the generic vDSO implementation to the aarch64 vDSO data page.
The _vdso_rng_data required data is placed within the _vdso_data vvar
page, by using a offset larger than the vdso_data.
The vDSO function requires a ChaCha20 implementation that does not write
to the stack, and that can do an entire ChaCha20 permutation. The one
provided uses NEON on the permute operation, with a fallback to the
syscall for chips that do not support AdvSIMD.
This also passes the vdso_test_chacha test along with
vdso_test_getrandom. The vdso_test_getrandom bench-single result on
Neoverse-N1 shows:
vdso: 25000000 times in 0.783884250 seconds
libc: 25000000 times in 8.780275399 seconds
syscall: 25000000 times in 8.786581518 seconds
A small fixup to arch/arm64/include/asm/mman.h was required to avoid
pulling kernel code into the vDSO, similar to what's already done in
arch/arm64/include/asm/rwonce.h.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
The chacha vDSO selftest doesn't check the way the counter is handled by
__arch_chacha20_blocks_nostack(). It indirectly checks that the counter
is writen on exit and read back on new entry, but it doesn't check that
the format is correct. When implementing this function on powerpc, I
missed a case where the counter was writen and read in wrong byte order.
Also, the counter uses two words, but the tests with a zero counter and
uses a small amount of blocks, so at the end the upper part of the
counter is always 0, so it is not checked.
Add a verification of counter's content in addition to the verification
of the output.
Also add two tests where the counter crosses the u32 upper limit. The
first test verifies that the function properly writes back the upper
word, the second test verifies that the function properly reads back the
upper word.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Without -O2, the generated code for testing chacha function is awful.
GCC even implements rol32() as a function of 20 instructions instead of
just using the rotlwi instruction.
~# time ./vdso_test_chacha
TAP version 13
1..1
ok 1 chacha: PASS
real 0m 37.16s
user 0m 36.89s
sys 0m 0.26s
Several other selftests directory add -O2, and the kernel is also
always built with optimisation active. Do the same for vDSO selftests.
With this patch the time is reduced by approximately 15%.
~# time ./vdso_test_chacha
TAP version 13
1..1
ok 1 chacha: PASS
real 0m 32.09s
user 0m 31.86s
sys 0m 0.22s
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Hook up the generic vDSO implementation to the LoongArch vDSO data page
by providing the required __arch_chacha20_blocks_nostack,
__arch_get_k_vdso_rng_data, and getrandom_syscall implementations. Also
wire up the selftests.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Acked-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Unlike the check for the standalone x86 test, the check for building the
vDSO getrandom and chacaha tests looks at the architecture for the host
rather than the architecture for the target when deciding if they should
be built. Since the chacha test includes some assembler code this means
that cross building with x86 as either the target or host is broken.
There's also some additional complications, where ARCH can legitimately
be either x86_64 or x86, but the source code we need to compile lives in
a directory path containing arch/x86. The standard SRCARCH variable
handles that. And actually, all these variables and proper substitutions
are already described in tools/scripts/Makefile.arch, so just include
that to handle it.
Similarly, ARCH=x86 can actually describe ARCH=x86_64,
just with CONFIG_64BIT, so we can't rely on ARCH for selecting
non-32-bit tests. For that, check against $(ARCH)$(CONFIG_X86_32). This
won't help for people manually running this inside the vDSO selftest
directory (which isn't really supported anyway and has problems on
various archs), but it should work for builds of the kselftests, where
the CONFIG_* variables are defined. On x86_64 machines,
$(ARCH)$(CONFIG_X86_32) will evaluate to x86. On arm64 machines, it will
evaluate to arm64. On 32-bit x86 machines, it will evaluate to x86y,
which won't match the filter list.
Reported-by: Mark Brown <broonie@kernel.org>
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Linking to libsodium makes building this test annoying in cross
compilation environments and is just way too much. Since this is just a
basic correctness test, simply open code a simple, unoptimized, dumb
chacha, rather than linking to libsodium.
This also fixes a correctness issue on big endian systems. The kernel's
random.c doesn't bother doing a le32_to_cpu operation on the random
bytes that are passed as the key, and consequently neither does
vgetrandom-chacha.S. However, libsodium's chacha _does_ do this, since
it takes the key as an array of bytes. This meant that the test was
broken on big endian systems, which this commit rectifies.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Having the prototype for __arch_chacha20_blocks_nostack in
arch/x86/include/asm/vdso/getrandom.h meant that the prototype and large
doc comment were cloned by every architecture, which has been causing
unnecessary churn. Instead move it into include/vdso/getrandom.h, where
it can be shared by all archs implementing it.
As a side bonus, this then lets us use that prototype in the
vdso_test_chacha self test, to ensure that it matches the source, and
indeed doing so turned up some inconsistencies, which are rectified
here.
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
After verifying that vDSO getrandom does work, which ensures that the
RNG is initialized, test to see if it also works inside of a time
namespace. This is important to test, because the vvar pages get
swizzled around there. If the arch code isn't careful, the RNG will
appear uninitialized inside of a time namespace.
Because broken code makes the RNG appear uninitialized, test that
everything works by issuing a call to vgetrandom from a fork in a time
namespace, and use ptrace to ensure that the actual syscall getrandom
doesn't get called. If it doesn't get called, then the test succeeds.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
When building with clang, there's this warning:
vdso_test_getrandom.c:145:40: warning: omitting the parameter name in a function definition is a C23 extension [-Wc23-extensions]
145 | static void *test_vdso_getrandom(void *)
| ^
vdso_test_getrandom.c:155:40: warning: omitting the parameter name in a function definition is a C23 extension [-Wc23-extensions]
155 | static void *test_libc_getrandom(void *)
| ^
vdso_test_getrandom.c:165:43: warning: omitting the parameter name in a function definition is a C23 extension [-Wc23-extensions]
165 | static void *test_syscall_getrandom(void *)
Add the named ctx parameter to quash it.
Reported-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
vdso_test_correctness test fails on powerpc:
~ # ./vdso_test_correctness
...
[RUN] Testing clock_gettime for clock CLOCK_REALTIME_ALARM (8)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
[RUN] Testing clock_gettime for clock CLOCK_BOOTTIME_ALARM (9)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
[RUN] Testing clock_gettime for clock CLOCK_SGI_CYCLE (10)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
...
[RUN] Testing clock_gettime for clock invalid (-1)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
[RUN] Testing clock_gettime for clock invalid (-2147483648)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
[RUN] Testing clock_gettime for clock invalid (2147483647)...
[FAIL] No such clock, but __vdso_clock_gettime returned 22
On powerpc, a call to a VDSO function is not an ordinary C function
call. Unlike several architectures which returns a negative error code
in case of an error, powerpc sets CR[SO] and returns the error code
as a positive value.
Define and use a macro called VDSO_CALL() which takes a pointer
to the function to call, the number of arguments and the arguments.
Also update ABI vdso documentation to reflect this subtlety.
Provide a specific version of VDSO_CALL() for powerpc that negates
the error code on return when CR[SO] is set.
Fixes: c7e5789b24 ("kselftest: Move test_vdso to the vDSO test suite")
Fixes: 2e9a972566 ("selftests: vdso: Add a selftest for vDSO getcpu()")
Fixes: 693f5ca08c ("kselftest: Extend vDSO selftest")
Fixes: b2f1c3db28 ("kselftest: Extend vdso correctness test to clock_gettime64")
Fixes: 4920a2590e ("selftests/vDSO: add tests for vgetrandom")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Running vdso_test_correctness on powerpc64 gives the following warning:
~ # ./vdso_test_correctness
Warning: failed to find clock_gettime64 in vDSO
This is because vdso_test_correctness was built with VDSO_32BIT defined.
__powerpc__ macro is defined on both powerpc32 and powerpc64 so
__powerpc64__ needs to be checked first in vdso_config.h
Fixes: 693f5ca08c ("kselftest: Extend vDSO selftest")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Following error occurs when running vdso_test_correctness on powerpc:
~ # ./vdso_test_correctness
[WARN] failed to find vDSO
[SKIP] No vDSO, so skipping clock_gettime() tests
[SKIP] No vDSO, so skipping clock_gettime64() tests
[RUN] Testing getcpu...
[OK] CPU 0: syscall: cpu 0, node 0
On powerpc, vDSO is neither called linux-vdso.so.1 nor linux-gate.so.1
but linux-vdso32.so.1 or linux-vdso64.so.1.
Also search those two names before giving up.
Fixes: c7e5789b24 ("kselftest: Move test_vdso to the vDSO test suite")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
If the getrandom test compiles for an arch, don't exit fatally if the
actual cpu it's running on is unsupported.
Suggested-by: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
